I ws looking through the BCM website yesterday to get some info on the Mk 12. The MSRP of the upper alone is ~$1275. The MSRP of the plain jane M-4 was ~475. Now I realize that a match grade barrel, and hand fitting will drive up cost. But examining the specs, I couldn't find anything that, in my mind, justified a price increase of 250 percent. Is BCM the only manufacturer of the M 12?? What am I missing?